The blue-collar wing of the Republican primary electorate has consolidated around one candidate. The party’s white-collar wing remains fragmented.It resembles Fox News leading all others in the ratings. Fox has a monopoly on the conservative half of the electorate, all other outlets split the liberal half. You don't have to guess who always wins the rating battle, Fox does.
If Brownstein is correct, Trump has a monopoly on the blue collar half of GOP voters, all of the other candidates split the white collar half. Trump leads, of course. A reasonable conclusion is that as others fall by the wayside, their supporters will coalesce around someone other than Trump.
In 2012 Romney appealed to the white collar wing of the GOP, many of the blue collar wing didn't vote for either candidate, stayed home. In 2016 we could see a situation in which substantial numbers of white collar Republicans abstain from voting, unable to stomach either major party nominee.
If the party cannot find candidates who appeal to both sides of our electorate, we may spend a long time in opposition, grumbling about gridlock. Perhaps Trump, an intuitive marketer, can figure out how to also appeal to the party's more educated half.